1. Field of the Invention
The present invention relates to a connector for connecting flexible substrates to electrical circuits. E.g., a flexible flat cable (FFC) or a flexible printed circuit substrate (FPC). More specifically, the present invention relates to a connector for connecting flexible substrates that allows a flexible substrate to be connected using low or zero insertion force.
2. Description of the Related Art
Conventionally, flexible substrate connectors serve multiple functions including electrically connecting FFCs and FPCs to each other, providing a relay connection between the two, or electrically connecting either one to a circuit substrate mounting electronic parts.
Since flexible substrates are flexible, flexible substrate connectors typically use a ZIF (zero insertion force) structure. ZIF structures allow flexible substrates to be inserted in a connector with low insertion force without exerting a contact pressure. After the flexible substrate is inserted, contact with the connector""s contacts is made using a predetermined contact pressure. This contact provides a stable electrical connection.
In conventional flexible substrate connectors equipped with a ZIF structure, contact sections of multiple contacts extend into an insertion opening of a housing. A slider attaches to the insertion opening and can move forward and back. When the slider is drawn outward from the insertion opening, a space for the insertion of the flexible substrate is provided. This space allows the flexible substrate to be inserted using a low insertion force without receiving contact pressure from the contacts.
After conventional insertion, the slider is inserted into the insertion opening. The slider presses the flexible substrate toward the contact sections, resulting in adequate contact pressure with the contacts. During conventional release, the slider is withdrawn and the space around the flexible substrate allows the flexible substrate to be removed without receiving contact pressure from the contacts.
In this type of conventional connector equipped with a ZIF structure, the slider is inserted along the direction of the flexible substrate. The ZIF structure is thus difficult to use since the flexible substrate gets in the way. Further, difficulty exists since the slider is held from both sides while inserted into or removed from the insertion opening. This insertion or removal requires operating space on either side of the connector. The requirement for additional space limits printed circuit substrate density.
Referring now to FIG. 9, a conventional flexible substrate connector 100 including a ZIF structure, employs a pivotable lever 102 in place of the slider described above.
Connector 100 includes a housing 101 formed from an insulative plastic resin and mounted on a printed circuit substrate (not shown). A series of contacts 103 attached to housing 101. Lever 102 formed from an insulative plastic resin.
Contacts 103 are stamped from a conductive metal plate and each includes a contact section 103a, a leg 103b and a support 103c. Contact section 103a is positioned in a cantilevered manner to contact a conductive pattern (not shown) formed on flexible substrate 130. Leg 103b connects with solder to the circuit pattern on the printed circuit substrate(not shown). Support 103c engages lever 102.
Housing 101 includes an insertion opening 104 formed to receive flexible substrate 130. Each contact 103 is attached at a pitch corresponding to the circuit pattern formed on flexible substrate 130 so that contact section 103a extend into insertion opening 104.
The base end of lever 102 is bent to form a U-shaped cross-section with an inner perimeter surface formed as an arc to engage support 103c of contact 103, and pivot around support 103c. An outer perimeter surface of lever 102 is formed with a recessed surface 105a and a projected surface 105b around the rotation axis of the lever 102.
During connection, lever 102 is pivoted vertically and flexible substrate 130 is inserted into insertion opening 104 of housing 101. When flexible substrate 130 is inserted, a lowermost portion of recessed surface 105a of lever 102 initially extends into insertion opening 104. This action forms a space between recessed surface 105a and contact section 103a of contact 103a and allows flexible substrate 130 to be inserted. Flexible substrate 130 can thereby be inserted without receiving initial contact pressure from contact section 103a. 
After flexible substrate 130 is inserted, lever 102 is pivoted to a closed position and projected surface 105b presses against the upper surface of flexible substrate 130. This pressing causing contact section 103a to flex downward and results in an elastic contact with a predetermined contact pressure between contact section 103a and the conductor pattern of flexible substrate 130.
During removal, lever 102 is pivoted in the opposite direction to an open position. This pivoting action forms a space in insertion opening 104 so that flexible substrate 130 can be removed without receiving contact pressure from contact section 103a. 
With connector 100 equipped with a ZIF structure and lever 102, lever 102 can be operated without being obstructed by the now inserted flexible substrate 130. Since the insertion-removal operation is performed from above connector 100, there is no need to provide additional operating space on either side of connector 100.
However, this type of pivoting flexible substrate connector 100 uses the difference in height from the rotation axis between recessed surface 105a and projected surface 105b. This difference in height allows flexible substrate 130 to press toward contact 103, providing a predetermined contact pressure with contact section 103a. Forming a projected surface 105b to provide contact pressure with a large height difference at the base end of lever 102 is difficult. Connector 100 thereby requires either a larger size or a reduction in contact pressure since a large height difference could not be provided.
Lever 102 and flexible substrate 130 only contact along projected surface 105b. This minimal contact allows flexible substrate 130 to be easily pulled out with a minimal pulling force. Easy removal of flexible substrate 130 would rotate lever 102 itself, thus requiring a stopper (not shown) to prevent lever 102 from rotating as a safety backup.
Additionally, where contacts 103 are attached with a narrow pitch in housing 101, contact sections 103a are exposed in insertion opening 104 in a longitudinally staggered manner along the insertion direction. Since pressure on flexible substrate 130 is applied only at one position along projected surface 105b it is difficult to provide an elastic contact with flexible substrate 130 having uniform contact pressure. Where two different contact types (not shown) are used, uniform elastic contact pressure is very difficult.
An additional negative to this type of design is that action of projected surface 105b tends to wear out and distort contact section 103a and contacts 103 over time. A final negative to the design is that one side of flexible substrate 130 is dominated by lever 102 thereby providing a design restricting contact sections 103a to a single side of flexible substrate 130.
It is an object of the present invention to provide a connector for providing stable electrical connection between a flexible substrate and a circuit.
It is an object of the present invention to provide a connector for connecting flexible substrates that does not require operating space on either side of a housing.
It is another object of the present invention to provide a device that allows a lever to operate without interference from a flexible substrate.
It is another object of the present invention to provide a device that prevents a connected flexible substrate from being easily removed from a connector.
It is another object of the present invention is to provide a flexible substrate connector that allows a uniform-pressure elastic contact with a flexible substrate even where the contacts are attached to a housing in a staggered manner.
Briefly stated the present invention relates to a connector for securely and electrically connecting flexible substrates requires zero insertion force (ZIF) and includes a slider, a housing and a lever. The housing houses electrical contacts and includes an insertion opening to receive the flexible substrate. The slider includes a pressing plate and securing projections. The slider and lever operate to slide the slider adjacent the housing and urge the pressing plate into the insertion opening. The securing projections secure the slider and the pressing plate presses the flexible substrate against the contacts establishing stable electrical connection. The connector provides uniform contact pressure, minimizes operating space, and eliminates interference from the flexible substrate.
According to an embodiment of the present invention, there is provided an electrical connector for connecting a pattern of conductors in a flexible flat cable to a circuit comprising: a housing, the housing including a slot for receiving an end of the flexible flat cable, a plurality of contacts in the housing alignable with the pattern of conductors when the end is inserted into the slot, a slider having a pressing plate thereon, the pressing plate being insertable into the slot adjacent the flexible flat cable, and at least one of the housing and the pressing plate having a shape which urges the pressing plate into firm contact with a surface of the flexible cable as the pressing plate is inserted, whereby the pattern of conductors is urged into stable electrical contact with the plurality of connectors and the housing provides a minimum profile.
According to another embodiment of the present invention there is provided an electrical connector, further comprising: a first and a second guide frame on the housing, a first arm and a second arm on the slider, and the first arm and the second arm slidably engaging each respective the first and the second guide frame, whereby the housing guides the slider into uniform close contact.
According to another embodiment of the present invention there is provided an electrical connector, further comprising: a lever, a first and a second pivot arm on the lever, a first shaft extending from each the first and the second pivot arm, each the first shaft rotatably joining the lever to the housing, whereby the lever is operable relative to the housing and provides a narrow profile to the electrical connector, and the lever at a first side of the housing after the pressing plate is inserted whereby the lever provides protection to the plurality of contacts.
According to another embodiment of the present invention there is provided an electrical connector, further comprising: an open position and a closed position on the slider, and the lever engagable with the slider and operating the slider between the open position and the closed position, whereby the lever urges the slider into uniform close contact with the housing as the pressing plate is inserted in the slot.
According to another embodiment of the present invention there is provided an electrical connector, further comprising: a front cam surface on each the first and the second pivot arm, a rear cam surface on each the first and the second pivot arm, a front follower surface on the first and the second arm of the slider, a rear follower surface on the first and the second arm of the slider, each the front cam surface engagable with each the front follower surface during an opening action of the slider, and each the rear cam surface engagable with the rear follower surface during a closing action of the slider to urge the slider into the uniform close contact.
According to an embodiment of the present invention there is provided an electrical connector for connecting a pattern of conductors in a flexible substrate to a circuit comprising: a housing, a plurality of contacts in the housing for electrical connection to the circuit, the housing including means for receiving the flexible substrate in a clearance position in the housing, the means for receiving including means for aligning the pattern of conductors with the plurality of contacts when an end of the flexible substrate is received into the housing, means for engaging the flexible substrate to force the pattern of conductors into firm electrical connection with the plurality of contacts, and at least one of the housing and the means for engaging having a shape which urges the pattern of conductors into secure electrical connection with the plurality of contacts in a direction perpendicular to an insertion direction whereby the electrical connector minimizes operating space, eliminates interference from the flexible substrate and provides uniform contact pressure.
According to another embodiment of the present invention there is provided an electrical connector, further comprising: a slider in the means for engaging, the slider slidably engaging the housing, a pressing plate on the slider slidably insertable in the means for receiving, and the pressing plate resiliently urging the pattern of conductors into secure electrical connection with the plurality of contacts.
According to another embodiment of the present invention there is provided an electrical connector, further comprising: means for operating the slider between a projected position and a recessed position, the means for operating providing a uniform insertion force along a width direction of the flexible substrate during engagement.
According to another embodiment of the present invention there is provided an electrical connector, further comprising: a lever in the means for operating, the lever engaging the slider to operate the slider between the projected position and the recessed position, and the lever receiving a closing force and magnifying the closing force applied to the slider thereby maximizing the urging and permitting the electrical connection to the circuit with a minimum effort.
According to an embodiment of the present invention there is provided an electrical connector for connecting a patter of conductors in a flexible substrate to a circuit, comprising: a housing, the housing including a slot for receiving an end of the flexible substrate, a plurality of contacts in the housing alignable with the pattern of conductors when the end is inserted into the slot, a slider having a pressing plate thereon, the pressing plate being insertable into the slot adjacent the flexible substrate, at least one of the housing and the pressing plate having a shape which urges the pressing plate into firm contact with a surface of the flexible substrate as the pressing plate is inserted whereby the pattern of conductors is urged into stable electrical connection with the plurality of contacts, means for operating the slider between a projected position and a recessed position, the means for operating providing a uniform insertion force along a width direction of the flexible substrate during insertion, a lever in the means for operating, the lever engaging the slider to operate the slider between the projected position and the recessed position, and the lever magnifying a closing force applied to the slider thereby maximizing the urging and permits the electrical connection to the circuit with a minimum effort.
According to an embodiment of the present invention there is provided a flexible substrate connector for connecting a pattern of conductors in a flexible substrate to a circuit, comprising: a housing, a plurality of contacts in the housing for electrically connecting the circuit, an insertion slot in the housing for receiving an end of the flexible substrate, the plurality of contacts alignable with the pattern of conductors when the end is inserted into the slot, a slider slidably engaging the housing, a pressing plate on the slider slidably insertable in the housing through the insertion slot adjacent the flexible substrate, a lever rotatably engaging the housing, the lever camably engaging the slider to operate the slider between an inserted position and a closed position whereby the lever provides a uniform engaging force along a width direction of the slider during insertion and the flexible connector minimizes operating space, and at least one of the housing, the pressing plate, and the plurality of contacts having a shape which urges the pressing plate into firm contact with a surface of the flexible substrate as the pressing plate is inserted whereby the pattern of conductors is urged into stable electrical contact with the plurality of contacts.
According to another embodiment of the present invention there is provided a flexible substrate connector, further comprising: the plurality of position slits having a pitch corresponding to a pitch of the pattern of conductors, a contact section and an attachment section on each the contact, the contact sections having a shape enabling elastic engagement with the pattern of conductors, the plurality of contacts arrayed along a width direction of the housing in at least a first row, a plurality of position slits in the housing adjacent the insertion slot, and each the attachment section engagable with each the position slit whereby the plurality of contacts is firmly retained in the housing in positions corresponding to the pattern of conductors.
According to another embodiment of the present invention there is provided a flexible substrate connector, further comprising: a first arm and a second arm on the slider, a first and a second guide frame on the housing, and the first and the second guide frame slidably guiding the first and the second arm of the slider during insertion whereby the slider maintains an aligned relation between the pressing plate, the slider, and the housing.
According to another embodiment of the present invention there is provided a flexible substrate connector, further comprising: a first securing projection on each the first arm and the second arm, a first securing slit on each the first and the second guide frame, and each the first securing projection slidably retained within each the first securing slit during operation whereby the slider is prevented from separating from the housing and the flexible substrate connector has a minimum size.
According to another embodiment of the present invention there is provided a flexible substrate connector, further comprising: a first and a second pivot arm on the lever, a bounded hole in the housing opposite each the first and the second pivot arm, a pivot shaft on each the first and the second pivot arm engaging the bounded hole and rotatably connecting the lever to the housing, a front cam surface on each the first and the second pivot arm, a rear cam surface on each the first and the second pivot arm, a front follower surface on each the first and the second arm, a rear follower surface on each the first and the second arm, each the front cam surface engaging each the front follower surface during the insertion and driving the slide to the inserted position, and each the rear cam surface engaging each the rear follower surface during an opening operation of the slider, whereby the lever cam-ably engages the slider and operates the slider between the inserted position and the closed position and provides the uniform engaging force along a width direction of the slider in a minimum of space.
According to another embodiment of the present invention there is provided a flexible substrate connector, wherein: each the first and the second guide frame extend from opposite sides of the housing to an end adjacent the plurality of contacts whereby the plurality of contacts is protected from lateral damage during use and attachment to the circuit, and the lever at the closed position of the slider extending above the end of the plurality of contacts whereby the plurality of contacts is protected from vertical damage during use and attachment to the circuit.
According to another embodiment of the present invention there is provided a flexible substrate connector, wherein: the plurality of contacts is arrayed in at least the first and a second row along the width direction of the housing.
According to an embodiment of the present invention there is provided a flexible substrate connector, comprising: a housing containing a plurality of electrically conductive contacts for electrically connecting to a printed circuit substrate, the plurality of contacts elastically deformable in a direction perpendicular to an insertion direction, the housing including an insertion slot formed for receiving a flexible substrate with a conductor pattern adjacent the plurality of contacts, a slider slidably engagable with the housing, the slider including a pressing plate member for slidably inserting in the housing, lever means for urging the pressing plate member into the housing, the pressing plate member pressing the plurality of contacts against the conductor pattern to secure firm electrical connection to the printed circuit substrate, the pressing plate member providing resilient urging to the flexible substrate in a direction perpendicular to the insertion direction, and the plurality of contacts electrically connecting the flexible substrate to the printed circuit substrate whereby the flexible substrate is firmly retained in the housing with zero insertion force and is securely and elastically retained in the housing to ensure stable electrical contact.